Recently in the field of photographic print, for the purpose of shortening delivery date and improving productivity of printing process, a method of shortening printing time has employed by using silver halide photographic material with high silver chloride content and rapid development. However, since development speed of silver chloride is remarkably fast, it is found that it is difficult to maintain continuous gradation from highlight to shadow portions of the characteristic curve, and that the curve tends to irregularly bend depending upon the processing condition.
Against this disadvantage, a method, whereby it is possible to obtain a characteristic curve with an expanded straight portion from highlight to shadow, by using a silver halide emulsion in which two or more kinds of silver halide grains with different sensitivities are mixed at a suitable ratio, has been proposed and the effect thereof has been recognised.
However, it has been found out when the method for improving gradation characteristics by mixing these emulsions, is applied, especially to a silver halide emulsion sensitized in the blue-light, variation in the gradation at the time of exposure is often seen against the change of the temperature, and thus improvement in the expansion of gradation, which is a main object of the present invention, cannot be achieved.
In view of the state of the art, the appearance of a light-sensitive silver halide photographic material for print which is applicable to rapid process and has improved gradation has long been waited.